Why the speaker is unusually vulnerable at the general election

THE shoppers in Buckingham's modest street market look bemused as a prospective parliamentary candidate, John Stevens, tells them: “You can bring down the speaker of the House of Commons!” Some tell him they will vote for the incumbent, John Bercow, although he did not come out of the parliamentary-expenses scandal with much credit. Most are happy to take the leaflets Mr Stevens proffers. Respect for politicians is not much in evidence in this prosperous market town. “They're all crooks, but Mr Bercow's a local man,” says Phillip Dillow. Yet his son, Edward, chips in: “I won't vote for nobody who steals. If I did that on benefits I'd be in jail by now.”

Mr Bercow, a Conservative, was first elected for the constituency in 1997. He became speaker of the House of Commons last year, when the previous incumbent, Michael Martin, was forced out in the row over parliamentary expenses. In theory his job should be safe: in 2005 he held his seat with 57% of the vote. And neither Labour nor the Liberal Democrats is putting up a candidate. The speaker is, by tradition, elected unopposed.

Instead Mr Bercow faces a fierce, personal and as yet unpredictable fight. Three independent candidates are standing, as are an activist in the British National Party and Nigel Farage, who in the autumn stood down as leader of the United Kingdom Independence Party (UKIP) to concentrate on the tussle in Buckingham. Perhaps predictably in this comfortable and overwhelmingly white constituency, all are on the right of the political spectrum.

One reason for the plethora of challengers is that Mr Bercow lacks support within his own party. Only a handful of Conservative MPs voted for him as speaker: one constituent says he was chosen by Labour as a “practical joke”. The feeling that he is a Labour sympathiser has been strengthened by the fact that his wife is standing as a Labour candidate in the local elections in London. The Conservatives' leader, David Cameron, has threatened to deselect any local activist who openly supports anyone but Mr Bercow. Even so, some well-placed Tory officials and party members are effusive, even if only in private, about Patrick Phillips, a former high sheriff of the county and rival candidate.

Mr Bercow's role in the expenses scandal has also hurt him. He “flipped” his second-home designation, avoiding capital-gains tax (which he later paid) and had to repay around £1,000 of expenses after a parliamentary investigation. Campaign literature for Mr Stevens, a former Tory MEP who says he was encouraged to stand by George Walden, Mr Bercow's predecessor in the seat, makes much of the speaker's complicated expenses. Its other theme is the third cause for unrest in Buckingham: the traditional disenfranchisement of voters in the speaker's constituency.

Mr Bercow also faces a serious challenge from UKIP's Mr Farage. A vote for him, Mr Farage says, is a vote for a clean man untainted by Westminster politics: “There are no big parties to vote for and the speaker who is seeking re-election is the symbol of the current political class.” But Mr Farage has faced expenses scandals inside his own party, and a recent outburst in the European Parliament has cooled the reception he gets on many of the politer doorsteps in Buckingham.

According to Mr Phillips, Mr Farage recently invited himself round to tea to ask him to stand down, rather than let Mr Bercow win against a split vote. Mr Phillips refused, saying that however angry his Conservative friends might be with Mr Bercow, they “did not want UKIP to establish a beach-head in Buckingham”. He sees the anti-Bercow vote being sliced up between a number of candidates, one of whom could oust the speaker, albeit on a minority of the vote.

Vernon Bogdanor, a professor of government at Oxford University, reckons that Mr Bercow is vulnerable. “The authority of the political class was undermined by the expenses scandal, and the authority of the role of speaker shattered,” he says. He thinks it unfair that voters in the speaker's constituency are disenfranchised, and proposes that the speaker, once elected, be shunted to a “notional constituency”, triggering a by-election in his original one.

Mr Bercow's friends, meanwhile, dismiss the disenfranchisement argument, saying that many constituents like the kudos of having the speaker as their MP. They point to their man's record as speaker in cleaning up Parliament, and comfort themselves that the “anti-Bercow vote is badly split”. If they are wrong, and Buckingham's constituents oust an incumbent speaker for the first time, it will send a pretty clear message to Westminster that business as usual is over.